This Raging Light by Estelle Laure

Can the best thing happen at the worst time?

Her dad went crazy. Her mom left town. She has bills to pay and a little sister to look after. Now is not the time for level-headed seventeen-year-old Lucille to fall in love. But love—messy, inconvenient love—is what she's about to experience when she falls for Digby Jones, her best friend's brother.
 
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